Adult ground beetles range in size from 1/16 to 3/8 inch long and have an elongate, somewhat flattened body shape. They are usually shiny black or black and brown in color, but some species are patterned or brightly colored. The head is narrower than the rest of the body and the legs are usually long and slender.
Ground beetle larvae vary from dirty white to dirty yellow to almost black in color. They have short legs and prominent mandibles.
Female ground beetles lay their eggs in protected places in the soil or beneath objects on the ground. The larvae have 3 growth stages (instars) and pupation takes place in the ground. The life cycle (egg to egg) takes one year in most cases, and adults live for 2-4 years. Ground beetles are terrestrial and are typically found on the ground, usually under something such as stones during the daytime.
A few species climb trees in search of food and may be seen during the daytime. Many species fly or crawl to lights at night. Most species are nocturnal or active at night. They typically enter structures by crawling under door thresholds or will fly in through open doors and windows at night when lights are on. Ground beetles are nuisance pests; they give off a very unpleasant odor when handled or crushed.
With few exceptions both adults and larvae are predaceous, so they are a beneficial group. Insects make up a large portion of their diet, including the larvae of many undesirable pest species such as cutworms and other caterpillars, beetle larvae, and maggots. Some feed on dead organic material.
What you can do: Preventative control consists mainly of removing objects under which ground beetles can hide during the day from within several feet of the building’s perimeter. Installing new door sweeps and tight threshold plates at all entrances can reduce entry to buildings. Changing exterior light bulbs from white to less attractive yellow or sodium vapor lamps helps. A vacuum cleaner is effective for removing the occasional ground beetle found indoors.
A Peoria Pest Eliminators pest management professional can reduce invasion by ground beetles, as well as many other crawling pests, via periodic applications of appropriate materials along the exterior perimeter of the foundation as well as adjacent soil, mulch and low vegetation. Such treatments are an important part of the Peoria Pest Eliminators regular service program as a protective barrier treatment around homes and other buildings.